1. 1.1 Measurements

2. Vocabulary Measurement – a determination of the amount of something
Unit – a fixed amount of something like a centimeter of distance
English System – measurement system used for everyday measurements in the United States
SI – International System of Units used by most countries for everyday measurement and used by the scientific community worldwide

3. Measurement and Units Measurements
Distance, Time, Mass, Volume, Weight, and Temperature
Must have a number and a unit

4. English System

5. SI

6. SI
Multiply or divide by powers of 10

7. 1.2 Time and Distance

8. Vocabulary Distance – the amount of space between two points
Length – a measured distance
Meter – a basic SI unit of length

9. Time Time is used in two ways What time is it? How much time?
The date or time of an event/moment in life
How much time?
A time interval, for example how long it takes to run a mile

10. Distance
Distance is measured in units of length

11. Basic Conversions How many minutes are in 1.5 hours?
Convert 330 minutes to hours.
Men in the age group need to be able to run a marathon in 3 hours and 10 minutes to qualify for the Boston Marathon. How many seconds is this?

12. 1.3 Converting Units

13. Converting SI Units 650 mm = ______ m 142 Km = _____ dm
754,000 cm = ____Km
0.23 m = _____Hm

14. Vocabulary
Conversion Factor – a ratio that has a value of one, and is used when setting up a unit conversion problem
Dimensional Analysis – a method of using conversion factors and unit canceling to solve a unit conversion problem

15. Dimensional Analysis 4.5 ft = ______ cm 175 yd = _______m
2.50 in = ________ mm
50 m = _______ yd

16. Dimensional Analysis – Part 2
4 gal = _____ fl. oz
3 year = _____ seconds
0.235 g = ________ mg
12 ton = ______ oz

17. Worksheet
Classwork: Complete the evens
Homework: Complete the odds

18. 1.4 Significant Digits

19. Vocabulary
Significant Digits – meaningful digits in a measured quantity
Accuracy – how close a measurement is to an accepted or true value
Precision – describes how close together or reproducible repeated measurements are
Resolution – refers to the smallest interval that can be measured

20. https://youtu.be/Gn97hpEkTiM

21. Significant Digits
It is impossible to make a measurement that is the exact true value of something
The first arrow clearly points to 4 cm
The second arrow is between 5 and 6 cm cm? 5.8 cm? If you wrote the answer as , it would be inaccurate because you cannot tell to that level of precision based on the ruler given

22. Which digits are significant?
Digits that are always significant:
Non-zero digits 13 has two significant digits
Zeros between two significant digits 104 has three significant digits
All final zeros to the right of a decimal point 4.0 has two significant digits
Digits that are never significant:
Leading zeros to the right of a decimal place has one significant digit
Final zeros in a number that does not have a decimal point 2000 has one significant digit
Note: A decimal point is used after a whole number ending in zero to indicate that the final zero IS significant. 50. cm has two significant digits

23. Calculations: Significant Digits
Your answer can have no more than the measurement with the least amount of significant digits.
Example:
What is the area of an 8.5 inch by 11.0 inch piece of paper?
A = length x width
A = 8.5 in x 11.0 in
A = 93.5 square inches
The smallest amount of significant digits is two, so the answer can only have two:
94 square inches

24. Classwork
P 23 # 1 – 7